CLEVELAND — Sen. Ted Cruz’s Texas-size political ambitions will be on full display Wednesday as the primary runner-up delivers a prime-time convention speech, but holds off on a full-throated endorsement of Republican nominee Donald Trump.

The conservative senator repeatedly clashed with Trump during a bitter primary fight, with the New York businessman mocking the lawmaker as “Lyin’ Ted.” With an eye toward 2020, Cruz’s team drafted a convention speech focusing on adherence to the Constitution, a calling card for conservatives and a perceived contrast with Trump.

Cruz has not endorsed Trump despite pleas for party unity from the campaign and party officials. Nor is he expected to in his speech, which was carefully screened by Trump campaign officials, the senator’s aides said.

Paul Manafort, Trump’s top campaign adviser, said Wednesday that he expects Cruz to address “the same kind of issues he talked about in the primaries,” adding that his message will be “consistent with what Mr. Trump is talking about.” Manafort’s words, however, suggested that relations between the two camps remain chilly.

He told CNN that “Cruz will be part of the campaign going forward, in what capacity I’m not sure, but his words will suggest that he is” behind Trump.

Before Trump even accepts the nomination, Cruz’s supporters as well as critics say undercurrents in Cleveland are emboldening the senator’s band of believers and stoking his 2020 prospects, should Trump lose in November.